Allegheny County Chief Executive Dan Onorato on Monday put in writing a pledge he made in July to cut mass transit costs.

He issued an executive order preventing Port Authority of Allegheny County from receiving any money generated by two proposed taxes until the transit agency cuts labor costs to his satisfaction.

A labor agreement covering 2,200 drivers and mechanics expires June 30, and contract talks are expected to take place over the next several months. The county would continue to make payments to Port Authority through June 30 but halt subsequent payments if the transit agency fails to reach a contract agreement to Onorato's liking, he said.

"Obviously, we're not going to let Port Authority shut down," Onorato said. "We do have some time to negotiate a contract."

County council members plan to vote next Tuesday on a budget and the two taxes -- a 10 percent levy on poured alcoholic drinks and a $2-per-vehicle surcharge on car rentals. Together, they would generate $27.7 million a year to benefit Port Authority.

If the county does not contribute that money, the state will not deliver its annual $184.4 million subsidy to Port Authority. Onorato proposes shifting the source of the authority's transit subsidy from property tax collections to money generated by the drink and car rental taxes.